Awesome, thanks @quochuy!
Just checked it, the error is actually only editing a post with an emoji, not creating it.
I cannot always reproduce it though. For instance if I edit this post all is fine.
I can still reproduce it on this post though: https://hiveblocks.com/bitcoin/@gaottantacinque/the-moment-you-find-out-your-btc-bip38-passphrase-does-not-work
In the latter please ignore the extra <i> around the emojis. The first time using those it allowed me to publish my edits but it worked only the first time. Then I had to use my hack to swallow the error.
👍